Frequently Asked Questions

Frequently asked questions

What happened in Lake Erie?

The Michigan Department of Environmental Quality (MDEQ) designated all the waters of Lake Erie under its jurisdiction as impaired for phosphorus pollution, because of its effect on “Other Indigenous Aquatic Life” (any aquatic animals that are not fish). Because phosphorus does not have a numeric limit under the state’s water quality standards, the state has instead set its recovery standard according to size and duration of harmful cyanobacteria (also known as blue-green algae) blooms in the lake.

The Domestic Action Plan MDEQ is submitting to EPA with this Impairment listing will be essentially the same plan submitted by MDEQ under an agreement signed in 2015 by Governor Snyder, Governor Kasich of Ohio, and Premier Wynne of Ontario to reduce phosphorus loading into the Western Lake Erie Basin by 40%. That Domestic Action Plan should be posted for public comment as early as December.

For now there is no plan to develop a Total Maximum Daily Load (TMDL) in Lake Erie, but MDEQ may develop one in the future, or EPA may require the state to do so, especially if the current plan does not reduce cyanobacteria blooms.

What does an impaired designation mean?

The federal Clean Water Act requires all states to report every two years to the EPA on their jurisdictional waters, and list any waters that have pollutant levels high enough to violate water quality standards. When a water is listed as Impaired, the state sends the proposed listing along with a Domestic Action Plan for recovery to EPA for approval, and then once the state receives approval, it moves forward with the Domestic Action Plan. Waters with high pollutant levels stay on the list as “Impaired” until either recovery efforts improve the water quality or until the state develops a TMDL to set strict pollution limits for water quality recovery.

What does a TMDL mean?

TMDL stands for Total Maximum Daily Load. It is a target number for the maximum amount of a pollutant that a water body can take without violating water quality standards. This includes pollutants that have a numeric limit, such as Parathion (an insecticide) with a chronic limit in waters of 0.013 parts per billion, and pollutants that have a narrative limit, such as phosphorus with a limit in waters described as “the extent necessary to prevent stimulation of growths of aquatic rooted, attached, suspended, and floating plants, fungi or bacteria which are or may become injurious to the designated uses of the surface waters of the state.”

Waters identified as impaired may be scheduled for a TMDL which sets the limit of a pollutant that a water can receive in order to recover enough to meet the state’s water quality standards. The TMDL is submitted to EPA along with Load Allocation limits for point and nonpoint sources, and a plan for what actions the state will take to reduce the pollutant level and a timeline for when those actions will take place. If the EPA approves the plan, the state then implements the TMDL and plan for that water and sets limits on the amount of pollutant entering the water.

Why is a 40% reduction in phosphorus the target?

Under the 1978 Great Lakes Water Quality Agreement as updated in 2012, protection of the Great Lakes falls under several Annexes. Annex 4 addresses nutrients entering the Great Lakes. The original agreement set targets for the maximum amount of phosphorus that can be put into each Great Lake without causing water quality problems. However, with algae blooms increasing in Lake Erie, the Annex 4 Task Team researched the problem, identified sources of phosphorus loading, and analyzed how much phosphorus would have to be reduced in Lake Erie to restore its water quality. That group determined in a 2015 report that a 40% reduction from the original agreement’s limit of 11,000 metric tons of phosphorus was needed to protect Lake Erie. That 40% reduction target was widely adopted by federal and state agencies.

Why are we targeting total phosphorus and not dissolved phosphorus?

Recent research by the Annex 4 Task Team in their report linked above, Heidelberg University in Ohio, and others, points to the problem of phosphorus pollution not being as simple as phosphorus entering the Lake. Phosphorus was always thought to be stuck to soil particles; if a farm practice stopped sediment from leaving the farm, it stopped the phosphorus. Now researchers are discovering that under the right conditions phosphorus can become dissolved (or reactive), meaning it separates from the soil and travels through groundwater and surface water where it becomes a much better food source for algae than phosphorus still attached to soil. It is not well understood why this happens – possibilities include:

High concentrations of phosphorus in surface layers of the soil that runs off

High concentrations of phosphorus throughout the soil layers, that moves into tile lines

Lower levels of other key soil components like sulfur, which helps phosphorus bind to the soil

Different forms of fertilizer that become more rapidly available

Timing of fertilizer application allowing too much to run off into waterways before it can bind to soil

Other explanations – there are many possibilities…

Because there is uncertainty about the way phosphorus becomes dissolved, because there is little historical data on dissolved phosphorus concentration, and because it is more difficult to monitor water for fractions of dissolved phosphorus than simply for total phosphorus, the Annex 4 Task Team and federal and state agencies chose to concentrate on total phosphorus. Reducing total phosphorus while continuing to research dissolved phosphorus and develop new management practices to prevent dissolved phosphorus loss, will start states toward water quality recovery instead of allowing Lake Erie’s condition to continue to worsen.

What is Ohio designating since most of Lake Erie is in their jurisdiction?

In the summer of 2016, the State of Ohio designated the nearshore portions of Lake Erie as Impaired for phosphorus pollution, but they made the designation under Drinking Water Standards instead of Other Indigenous Aquatic Life the way Michigan did. This means that Ohio’s Impaired waters are located in the first 100 yards from the Lake Erie shoreline, and 500 yards around any drinking water intakes in Ohio’s portion of Lake Erie.

Isn’t Michigan already working to improve the WLEB?

Yes. Within MDEQ’s report, total phosphorus was identified as the target nutrient for necessary reductions, with a 40 percent reduction goal of total phosphorus loads entering the WLEB to restore its ecological balance.

Michigan’s portion of the 2015 Collaborative Agreement between Michigan, Ohio, and Ontario, which forms the base of the Lake Erie Domestic Action plan, includes actions like:

Maintain the reductions achieved in the Detroit Water and Sewage Department (DWSD) discharge as a result of the tightened permit limits. This is the largest single point source discharge to Lake Erie.

Achieve reductions in the Wayne County Downriver Wastewater Treatment Plant discharge. This NPDES permit will be modified to include phosphorus limits consistent with the limits in the DWSD permit.

Achieve the target reductions in the Maumee River basin in Michigan.

Help with monitoring and understanding harmful algal blooms regarding presence, timing, and cause in Michigan waters, including the Great Lakes.

Help with understanding the role of invasive mussels in causing Lake Erie algae blooms and the effect of potential invasive mussel control options.

Understand the specifics regarding the Raisin River phosphorus reductions, share this success story, and continue to reduce nutrient loads that may contribute to site-specific watershed or seasonal fluctuations in water quality.

Farmers are encouraged to work toward full MAEAP verification if they aren’t already. Michigan law states that farms meeting MAEAP standards for all systems applicable to their farms have the presumption of meeting the obligations and practices for watershed pollutant loading determinations, or Total Maximum Daily Load (TMDL). This means if you are MAEAP verified in all the systems that apply to your farm, you will not have to take any additional actions to meet Load Allocation limits if Lake Erie is put under a TMDL.

Contact your local Conservation District to learn more about MAEAP.

How is the stewardship of Michigan farmers measured?

From 2013 through 2015, MAEAP has confirmed the implementation of conservation Best Management Practices (BMPS – see the chart below) on nearly 99,000 acres of cropland, or about 10 percent of the cropland, in the Michigan portion of the WLEB. This work is accomplished through farmers voluntarily participating in the MAEAP process.